Surgical procedures are usually used for treatment of cellular tissues requiring direct contact of target tissue with a medical instrument. Surgical procedures often lead to substantial trauma by exposing both the target and intervening tissue. Furthermore, precise placement of a treatment probe is difficult because of the location of a target tissue in the body or the proximity of the target tissue to easily damaged, critical body organs, nerves, or other components.
Destruction of cellular tissues in situ has been used in the treatment of many diseases and medical conditions alone or as an adjunct to surgical removal procedures. It is often less traumatic than surgical procedures and may be the only alternative where other procedures are unsafe. Ablative treatment devices have advantage of using a destructive energy which is rapidly dissipated and reduced to a non-destructive level by conduction and convection to forces of circulating fluids and other natural processes.
Devices using microwave energy, radiofrequency energy, ultrasound energy, cryogenic, and laser energy, and tissue destructive substances have been used to destroy malignant, benign and other types of cells and tissues from a wide variety of anatomic sites and organs. Tissues treated include isolated carcinoma masses and, more specifically, organs such as the prostate, glandular and stromal nodules characteristic of benign prostate hyperplasia. These devices typically include a catheter or cannula which is used to carry a radiofrequency electrode or microwave energy antenna through a duct to the zone of treatment and apply energy diffusively through the duct wall into the surrounding tissue in all directions.
Canker sores are also known as aphthous ulcerations or recurrent aphthae, which are painful sores usually formed in the mucus membrane of the mouth. The sores first appear as small red lesions which quickly whiten and then break down to form shallow ulcers. Many people, especially the small children with less immunity to ulcerations, experience the pain and discomfort of canker sores for a period from several days up to a couple of weeks. While the cause of canker sores has not been identified, several pharmaceutical approaches have been taken. They only mask the sources of the problem for temporary relief of pain and stress.
Price, Jr. in U.S. Pat No. 5,686,095 entitled "Method of treating canker sores" teaches a method by which a fluoroquinolone is topically applied to the ulcerous area. Similarly, Alliger in U.S. Pat. No. 5,516,799 entitled "Method of treating small mouth ulcers" teaches a method of using a simple alpha hydroxy organic acid. Marcus et al. in U.S. Pat. No. 5,182,104 entitled "Topical virucidal composition for treatment of mucocutaneous tissue" teaches a method of topically applying composition with a virucidal impact on mucocutaneous tissue, inactivation of herpes virus and human papilloma virus as manifested in cold sore, canker sores, warts, fever blisters lesions, aptheous ulcerations. Leeds in U.S. Pat. No. 4,466,956 entitled "Method of therapy for oral herpes simplex" discloses serial application of povidone-iodine and then application of anti-inflammatory agent. Hodosh in U.S. Pat. No. 4,191,750 entitled "Method for treating canker sores" discloses a method of applying a nitrate of potassium, lithium, sodium, magnesium, calcium or strontium. However, none of said patents disclose the method for treating canker sores by radiofrequency (RF) ablation or other energy treatment.
Of particular interest to the present invention are RF therapeutic protocols which have proven to be highly effective as used by electrophysiologists for tachycardia treatment, by neurosurgeons for the treatment of Parkinson's disease, and for neurosurgeons and anesthetists for other RF procedures such as Gasserian ganglionectomy for trigeminal neuralgia and percutaneous cervical cordotomy for intractable pains. Radiofrequency ablation, which exposes a patient to minimal side effects and risks, is generally performed after locating the treatment sore sites. Radiofrequency energy, when coupled with a temperature control mechanism, can supply precise energy to the device-to-tissue contact site to obtain the desired temperature for the optimal effects.
Imran in U.S. Pat. No. 5,281,218 entitled "Catheter having needle electrode for radiofrequency ablation" teaches a needle electrode attached on a catheter for radiofrequency ablation. Though a needle-like electrode is beneficial to ablate a tissue point for deep lesion, it is not disclosed that said needle electrode is possible to make an area ablation to cover the entire canker sores region with a temperature control means for radiofrequency therapy and capability for delivering therapeutic agent.
Edwards et al. in U.S. Pat. No. 5,456,662 entitled "Method for reducing snoring by RF ablation of the uvula" teaches a medical ablation method for reducing snoring wherein a flexible RF electrode wire is inserted into an uvula and RF energy is applied to the uvula tissue to cause internal lesions. Edwards et al. does not disclose a catheter to ablate an area having capability for simultaneously delivering therapeutic agent.
While a radiofrequency procedure using an existing electrode device has had promising results, the device is exposed to the tissue contact point and the heat only covers a small region, resulting in inefficient treatment of canker sores. Therefore there is a need for a new and improved device system and methods using the more controllable radiofrequency current for generating the needed heat to treat the desired broad region of the canker sores. During RF energy is applied to an electrode means or immediately after applying RF energy, the therapeutic agent, such as anti-inflammatory agent or virucidal drug, is delivered to the lesion sites. By designing a device with temperature control means and substance delivery capability, the canker sores can be treated therapeutically.